Spraying device for paints, varnishes, etc.



Oct. 11, 1932. w. HERMANN SPRAYING DEVICE FOR PAINTS, VARNISHES, ETC

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M/ZZZA' Oct. 11, 1932. w. HERMANN SPRAYING DEVICE FOR PAINTS, VARNISHES; ETC

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W. HERMANN SPRAYING DEVICE FOR PAINTS, VARNISHES, ETC

Oct. 11, 1932.

; Filed Oct. 24, 1927 3 Sheets-Sheet 3 Patented Oct. 11, 1932 UNITED STATES PATENT OFFICE WOLFGANG HERMANN, OI? CHICAGO, ILLINOIS, ASSIGNOR TO METAL SPECIALTIES MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS SPRAYING DEVICE FOR PAINTS, VARNISHES, ETC.

Application filed October 24, 1927. Serial No. 228,336.

This invention relates particularly to varnish-spraying devices, but the invention may be put to various analogous uses.

The primary object is to provide an eflicient, compact unit, which embodies a portable motor and compressor of such compactness and efliciency as to enable the outfit to be carried by the operator while performing the spraying operation.

Two embodiments of the invention are lllustrated in the accompanying drawings.-

One embodiment consists of a hand-carried unit comprising'a frame equipped at one end with a hand-grip and at the other end with a nozzle provided with means for supporting the varnish-can, and a rotary compressor and motor suspended from an intermediate portion of said frame, the compressor being disposed immediately beneath the frame and communicating with the nozzle through the medium of an air passageextending through the frame. In the other embodiment illustrated, designed for greater capacity, the combination compressor and motor is adapted to be supported on the person by means of a harness, and the nozzle is connected with the compressor by means of a short air-hose, the nozzle being equippedflnthis case, with a hand-grip as well as with means for suspending the can.

In the drawings Fig. 1 is a vertical sectional View of a hand-carried spraying-unit embodying the invention; Fig. 2, a broken vertical sectional view of a container, or varnish-can, which can be applied to the unit after removing the closure with which the varnish-can is equipped Fig. 3, a plan View of the combined compressor and motor taken as indicated at line 3 of Fig. 1, the frame which forms a closure for the upper end of the compressor chamber having been removed; Fig. 4, a broken plan sectional view taken as indicated at line 4 of Fig. 1; Fig. 5, a vertical section through the nozzle taken as indicated at line 5 of Fig. 1; Fig. 6, an enlarged broken sectional view taken as indicated at line 6 of Fig. 1; Fig. 7, a broken vertical sectional view taken as indicated at line 7 of Fig. 1; Fig. 8, a broken vertical sectional View illustrating a modified form of nozzle; Fig. 9, a broken transverse section taken as indicated at line 9 of Fig. 8; Fig. 10, a section taken as indicated at line 10 of Fig. 8; and Fig. 11, a View of a modified form of embodiment of the invention, in which embodiment the motor-compressor unit is adapted to be supported by the operator through the medium of a harness.

Referring to the embodiment illustrated in Figs. 1-7, A designates a framesmember equipped at one end with a depending pistolgrip handle A and equipped at the other end with a projecting nozzle A B, a motorcompressor unit depending from the framemember and having an axis parallel with the axis of the handle; and 'C, a liquid-container,

or can, detachably connected with the nozzle and having an axis parallel with the axis of the handle A, the motor-compressor unit being interposed between the handle and the liquid-container.

The arrangement and construction are such that the liquid-container, the motor-compressor frame, and the handle are in rigid relation, so that the handle can be gripped by the operator and the device, as a whole, can be thereby supported at arms length in the spraying operation. It has been demonstrated that such an outfit can be made so light, compact, and efiicient, as to serve effectively the purpose of spraying lacquers, varnishes, etc., while the combination outfit, as a whole, is carried in the hand of the operator as a spraying-gun.

In the illustration given, the frame A is provided at one end with a tubular boss 1, and the handle A is hollow, or tubular, the chamber 1 serving to house a switch 2, and the hollow handle permitting the passage therethrough of the electric cord 3.

The motor-compressor unit consists of a vertical electric motor B and a surmounting rotary compressor B The motor B comprises a vertical casing 4.- havinga lower end-cap 5 and an upper endcap 6 which is so formed as to provide a compressor-chamber 6; an armature 7 ournalled in the casing and having a shaft 7 whose upper end extends into the compressor-chamber ing, and the top-cap 6 of the motor-casing,

and is eccentrically disposed therein and threaded rods, or large cap-screws, 8 which rigidly to ether.

As has en stated, the top-cap 6 of the motor-casing is so formed as to provide therein the compressor-chamber 6 Th1s chamber is of cup-shape, having a circumferential wall 6" and a bottom wall 6, which, as shown, is equipped with a bearing through whlch the armature-shaft extends. The cap. 6 hasa ring-portion 6 connected by spaced flat ribs 6 with the circumferential wall 6 of the compressor-chamber. These ribs, or flanges, constitute a radiator, and are spaced apart to permit air to be circulated between them,

as indicated by the arrows in Figs. 1 and 3.

The motor-casing is provided with air-inlet passages 9, and the armature-shaft is equipped just below the radiator with a fan 10 which serves to circulate cooling. air through the spaces between the fins of the radiator.

The motor-casing is shown equipped in The frame-member A has .a portion 12 which constitutes a top-cap for the compressor-chamber. The frame-member is additionally secured to the walls of the compressor-chamber by means of cap-screws 13.

The motor-casing and top-cap 6 may be composed of aluminum, if desired. In the illustration given, the chamber 6*? is shown provided with a brass lining 14. Within the compressor-chamber 6 is a disk-like rotor 15 which is provided with a central bore which fits over the free upper end of the armature-shaft. The rotor is provided with a transverse pin 16 which engages a U-shaped cross-slot 17 in the upper end-surface of the armature-shaft.

The rotor 15 is concentric with relation to I the armature-shaft, but is eccentric with relation to the bore of the compressor-chamber. Preferably, the lining 14 is provided interiorly at one side with a semi cylindrical bearing-surface 14 which is struck on a radius which conforms to the radius of the rotor 15. Thus, the rotor has a curved-u plane contact with the wall of the compressor-chamber. The purpose is to provide against leakage'at this point.

The rotor 15 is provided with slots 15", which preferably are oblique, rather than radial. Within these slots are located sliding-vanes 15 whose outer ends contact with the inner circumferential Wall of the compressor-chamber. The use of springs to project the vanes hasbeen found unnecessary in practice, inasmuch as the centrifugal force will serve the purpose.

Through the bottom wall 6 of the compressor-chamber extends an inlet port 18 (Figs. 3 and 7); and through the framemember extends an air passage which receivesthe' compressed air through "a port connect the frame-member A, the motor-cas-n 19== communicating with the compressored above the axis of the rotor with a lubricant-chamber. 20 which is fitted with' a movable plug 20. The lubricant-chamber may be filled with felt, as shown, to absorb alimited amount of oil. A small passage 20 leads from the bottom of the lubricant-chamber to the compressor-chamber.

The .vanes 15 of the rotor may be formed of any suitable material. Preferably they are composed of hard fibre which has been boiled in paraffin. The lubricating device is designed to enable a very slight amount of lubricant to be gradually fed to the rotor.

The frame-member A is shown equipped upon its upper side with stiffening ribs 21 which serve also as radiating fins.

The chamber of the frame-member A is equipped with a removable top-plate 22 "23 adapted to be-introduced 'into'any suitable socket with which the wiring of a building is equipped. The motor-casing is equipped at its lower portion with a bracket 24 which has a split ring-portion 24 within which the lower portion of the handle A fits. The wires of the electric cord pass through a perforation 25 with which the handle is provided and between the members of the bracket 24, and enter the motor-casing through a ferrule 26 with which the lower end-cap 5 is provided. The handle A is further provided at its lower portion with a ferrule 27 through which the electric cord 3 extends.

It will be noted from Fig. 1 that the lower cap 5 of the motor-casing is equipped with tapped lugs 28 into which the lower ends of the large cap-screws 8 are screwed.

The nozzle A is provided at its base with a threaded reduced portion 29 which screws into a tapped boss 30 with which the framemember A is provided at its front end. The bore 31 of the nozzle communicates with the air-passage 19 of the frame-member A. The shank of the nozzle is provided witha shoulder 32, with a bearing-surface 33, with a threaded portion 34, withan intervening annulai' recess 35, and with a tip-portion 36. Thethreaded portion 34 is crossed by a longitudinal groove 37 affording a liquid-passage; and the nozzle is fitted with a hollow tip 38 which screws onto the threaded portion 34'. Through the interior nozzle-portions just described extends a small central Ill air-passage 39 which communicates with the larger passage 31. The construction provides for the central passage of compressed air; and the hollow tip 38 is provided at its extremity with an outlet passage 38 through which both liquid and compressed air may be sprayed.

From the nozzle depends a fitting 40 which has a ring-portion 40 which fits on the hearing 33. This ring-portion is clamped between the shoulder 32 and the removable hollow tip 38. The fitting is provided with a vertical liquid-passage 40 and is equipped with a liquid-tube 40. The fitting is also rovided at its lower end with a circular fiange 40 to which is secured a threaded cap 40 which screws onto the hollow threaded nipple 41 with which the top-wall 41 of the container C is equipped.

The container C may consist of a can for holding lacquer, or varnish. Such cans, filled with varnish,'are purchasable on the market. They come equipped with a removable cap 42, as illustrated in Fig. 2. When one 1 can has been emptied, another may replace it in the spraying outfit; or, if desired, the varnish, or lacquer, may be poured from the container in which it is purchased into the can with which the spraying outfit is equipped.

, The fitting 40 is shown equipped with a screw 43 for regulating the passage of liquid through the passage 40". It will be noted that when compressed air passes through the outlet passage 39, an induced flow of liquid through the passage 40 of the fitting 40 and through the passage 37 of the interior nozzlemember 36 occurs. The force of the air-current serves to spray the liquid in a well-known manner.

In the modified form of nozzle-device shown in Figs. 8 and 9, the nozzle is designed to throw the spray in the form of a fan. By a broadside movement of the nozzle, a large area can be quickly covered. In this form, the liquid is delivered through a central passage at the nozzle-tip, and is there struck by inclined air-currents which produce a fan-efl'ect of the spray, very much as an acetylene flame is produced.

In the modification of Figs. 8 and 9, the shank 44 of the nozzle is provided with a frusto-conical surface 45 and with a reduced extension 46 having an enlarged threaded portion 47 upon which is threaded a tubular member 48 having a frusto-conical surface 49 opposed to and spaced from the surface 45. A fitting 50 which supports a cap 51 is provided with a ring-portion 50 provided with frusto-conical surfaces. The member 46 is provided with an annular channel 52 which communicates through a radial channel 53 with a longitudinal liquid-passage 54 leading to the tip of the member 46. A liquid-passage 55 loads from the liquid-tube 56 through the fitting 50 and communicates through a reduced passage 57 with the annular liquid-passage 52.

The member 44 has an air-passage 61 from 62 which which radiate inclined passa es communicate with passages 63 extending through the ring-portion 50 of the fitting 50. The passages 63 communicate with air-passages 64 extending through the conical head of the member 48, and the air is thus conducted through an annular passage 65 between the member 46 and the member 48. The passage 65 communicates with an annular space 66 from which extends air-passages 67 disposed between the members 58 and 59. The member 59 is further provided with the outer air-passages 68 which are adapted to produce a fan-efiect on the spray, and with inner passages 69 adjacent the outer extremity of the tip-member 58 and adapted to aid in inducing the flow of liquid through the central passage 58. p

The ring-portion 50 of the fitting 50 is clamped between the conical surfaces 45 and 49 by screwing the member 48 tightly onto the threaded portion 47 of the member 46.

The nozzle-tip 59 can be rotated to any desired position and then clamped in that position by tightening the nut 60, it being noted that the outer nozzle-tip 59 has a bearing on the inner nozzle-tip 58, the inner nozzle-tip being fluted, or grooved, to provide the passages 67.

The form of nozzle shown in Figs. 8 and 9 may be used advantageously where it is desired to cover a large area with a comparatively thin coating. It may be used advantageously also in producing line effects by an edgewise movement of the fan-tail spray.

Sharp line efi'ects may be obtained by the use of a suitable stencil. In general, a higher degree of pressure is required for this form of work than is necessary where the conical spray is used, such as results in the use of the nozzle shown in Fig. 1.

The modified form of spraying outfit illustrated in Fig. 11 may be used where a greater capacity is required. Ordinarily, a high speed motor is employed; and where a spraying outfit of large capacity, suitable for covering larger areas quickly, is desired, the size of the motor and of the rotary compressor may be correspondingly increased. Above a certain limit, it may be desirable to support the combined motor and compressor from the operators body. and conduct the compressed air through a short hose to a spray-gun device, as shown in Fig. 11. In this figure, B designates a combined motor and compresvoir of moderate capacity.

sor; A designates a nozzle-device; and C designates a container depending from the nozzle-device.

The combined motor and compressor B is of the construction --.shown in Fig. 1, only slightly modified. The frame-member A is here replaced by a cap-disk A which serves to close the upper side of the compressorchamber. An outlet from the compressorchamber extends through a nipple 70 with which the cap-piece A is equipped; and the compressed air is taken from the nipple 70 through a short flexible hose 71 to the nozzle-' device A The combined motor and compressor B is supported by a harness D applied to the per son of the operator. The electric cord 72 has a conductor 7 3 leading to the switch-de vice 74, and thence back to the motor. The switch-device, in this case, preferably is mounted in the upper portion of a piston-grip 75 which is rigidly connected with the shank of the nozzle. The nozzle may be of the construction shown in Fig. 1, the fitting 40 serving to carry the liquid-container C: Thus, the handle 75, the nozzle, and the liquidcontainer are all held in rigid relation to each other.

In the constructionillustrated in Figs. 1-7, the air-passage 31 is of suflicient capacity to give a certain cushioning effect and produce a suitably steady air-stream at the tip of the nozzle. The same is true with respect to the air-passage 61 of the nozzle shown in Fig. 8; and in the construction shown in Fig. 11, the air-hose 71 itself serves as an air-reser- In the operation of the device, the liquid flows from the container only as an induced current produced bythe passage of the air,

and the apparatus is controlled simply by the switch-lever. That is, the induced flow of liquid starts immediately after the motor is started andceases when the motor is stopped. In the operation, a considerable amount of heat is generated, even in a small spraying outfit in which the chamber ofthe rotary compressor may have a diameter of about one and one-half to two inches. In larger outfits, where a more powerful motor and compressor are used, the amount of heat is correspondingly increased, especially where the pressure is. raised to say about twenty-five or thirty pounds. It is important, therefore, tov provide radiating surfaces in association with the compressor and to pro; vide means for circulating air past the radiating surfaces. The desired result is secured in a very satisfactory manner in the construction illustrated. The air-inlets leading to the fan may be so located as to draw the air past the armature from the lower end of the armature, or may be arranged in any other suitable manner.

After the spraying outfit has been used for applying lacquer, or varnish, for example, the passages in and about the nozzle may be cleaned by applying the nozzle-device to a can containing a solvent and spraying the solvent, through the nozzle. If a more thorough cleansing is desired, the parts of the nozzle may be readily separated for such purpose.

The frame-member A may be disconnected from the motor-compressor by removing the screws. The rotor may then be lifted out of the compressor-chamber and, if desired, the cap-member 6 may be removed from the motor-casing. The parts are readily assembled, and are easily accessible in case the replacement of any parts may become necessary.

The blades, or vanes, 15 are simply dropped into the slots in the rotor and rest on the bottom of the compressor-chamber, the upper and lower surfaces which engage the upper and lower edges of the vanes being formed by the top and bottom walls of the compressor-chamber. In case the vanes become worn, new ones can be substituted readily and at insignificant cost.

It may be added that the improved sprayin outfit is adapted to deliver the air very quickly following its compression, so that the air may issue from the nozzle in warm condition. This tends to improve the flow of lacquer, for example, and aids in the atomizing. Also, the warm air tends to aid in the quick drying of the lacquer.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible, in view of the prior art.

What I regard as new, and desire to secure by Letters Patent, is:

1. A hand-carried spraying-device comprising a frame provided with an air-passage, said frame being equipped at one end with a rigid depending handle and at the other end with a rigid projectingnozzle equipped with a depending container-attaching device, and a motor-com ressor unit depending from said frame and isposed between the handle and container-attaching device, the com pressor-chamber communicating through said frame with said nozzle.

.' 2. A hand-carried spraying-device comprising a motor-compressor unit, a nozzle projecting from the upper wall of the compression-chamber of said unit and equipped at one side thereof with a depending contamer-attaching device, and a handle at the upper end of said handle, and an electric prising a frame having at one end a nozzle equipped with a liquid-tube and a can-attaching member and having at the other end a depending hand-grip, a rotary compressor depending from said frame and disposed at an intermediate point between the handle and can-attaching member, and an electric motor depending from said compressor.

5. A hand-carried spraying-device comprising a frame-member adapted to serve as a cap-piece, a nozzle projecting from said frame-piece and equipped with a liquid-container supporting-device, a vertical motorcasing having an upper cap-piece providing a compressor-chamber, a rotor in said compressor-chamber, an armature in said motorcasing having a shaft extending into said compressor-chamber and connected with said rotor, said frame-member having an air-passage leading therethrough from the compressor-chamber to the nozzle, and a handle rigidly related to the motor-casing and located on the side of the motor-casing opposite that where the liquid-container supportingdevice is located.

6. A. hand-carried spraying-device comprising a frame-member serving as a cappiece and provided with an air-passage, a nozzle rigidly connected with said framemember and communicating with said passage, a liquid-container depending from said nozzle, a motor-casing depending from said frame-member and having a cap-piece affording a compressor-chamber and equipped with air-passages and radiating surfaces, an armature in said casing having a shaft extending eccentrically into the compressorchamber, a rotor mounted on said shaft, a fan mounted on said armature-shaft, below the cap-piece of the motor-casing, and a hand-grip rigidly related to the motor-casing and disposed opposite the liquid-container.

7. In combination, a frame-member havin a portion adapted to serve as a cap-piece an having an air-passage leading to one end of the frame-member, a nozzle rigidly connected with said frame-member and communicating with said air-passage, a liquid-container depending from said nozzle, a motor-compressor unit depending from said frame-,

member, said frame-member serving as a closure for the upper side of the compressorchamber, a hollow handle depending from the other end of said frame-member, a switch mounted in said frame-member adjacent the cord having a wire extending through the handle to the switch-member and thence through the handle to the motor.

8. In combination, a motor-casing having an upper cap-piece provided with air-passages and equipped with a compressor-chamher having an open upper end, an armature in said casing havin a shaft extending into the compressor-cham er, a rotor mounted on said shaft, a fan in said casing adapted to circulate air through the passages of the cappiece of the motor-casing, a frame-member extendin across the up er end of the compressor-c amber and at ording a cap-piece therefor, means detachably connecting the motor-casing to said frame-member, a nozzle projecting from said frame-member and equipped at one side of the motor-casing with a liquid-container, and a handle disposed at the other side of the motor-casing and rigidly related thereto.

9. In combination, a motor-casing having an upper cap-piece provided with air-passages and equipped with a compressor-chamber having an open upper end, an armature in said casing having a shaft extending into the compressor-chamber, a rotor mounted on said shaft, a fan in said casing adapted to circulate air through the passages of the cappiece of the motor-casing, a frame-member extendin across the upper end of the compressor-c hamber and afiording a cap-piece therefor, means detachably connecting the motor-casing to said frame-member, a nozzle projecting from said frame-member and equipped at one side of the motor-casing with a liquid-container and a handle disposed at the other side of the motor-casing and rigid ly related thereto, said handle being equipped with motor-controlling means.

10. In combination, a vertical electric motor, a rotary compressor surmounting the motor and having a rotor direct-coupled to the armature-shaft of the motor, a frame-member surmounting said compressor and forming a cap therefor, a nozzle rigidly connected with said frame-member, a liquid-container depending from said nozzle, and a handle rigidly related to said frame-member and to the casing of the motor and disposed opposite said hquid-container.-

11. A nozzle-device for a spraying outfit, comprisin a nozzle-shank provided with a frusto-conical surface and equipped with a reduced extension, an outer tubular member having threaded connection with said extension and provided with a frusto-conical surface, a fitting having a ring-portion interposed between said conical surfaces, a pas sage through the nozzle-shank and radiating passages therefrom opening at the frustoconical surface, passages through the ringportion of said fitting, passages through the conical portion of said tubular member leading to an annular passage between said extension and said tubular member, tip-members applied to said extension and to said tubular member and adapted to produce a fan-spray, and a central passage through -said extension communicating at 1ts rear end with an annular space between said ringportion and said extension, said annular space communicating through said ringportion with a liquid-passage leading through said fitting.

\ 12. A device of the character set forth comprising a handle having its upper end equipped with a forwardly projecting framemember serving as a compressor cap, a rotary I compressor secured to and depending from said cap, a nozzle mounted on said frame member and communicating with the chamber of said compressor, a container-supporting member depending from said nozzle and 20 equipped With a liquid tube, and an electric motor interposed between the container-supporting member and handle and having a shaft projecting upwardly into the compressor chamber and connected with the rotor of 25 said compressor.

WOLFGANG HERMANN. 

